This invention relates generally to vehicles and more particularly to covers for cargo beds.
Cargo beds on vehicles have always suffered from a dual objective: on the one hand, the user wants an open cargo bed since this allows easy loading and unloading; yet, on the other hand, there are times when the cargo requires protection from the elements and security from theft.
In an attempt to provide this protection, an assortment of caps, shells, or rigid covers have been developed which fully enclose the cargo bed. These shells provide for optimal protection from the elements and from theft; but, they are also heavy and extremely cumbersome to remove and store should the user desire an open cargo bed. Because of this, typically once the shell is attached to the vehicle, it is seldom removed.
To solve this problem, a variety of mechanisms have been developed which attempt to make the shell easier to remove and store. Some such mechanisms are described in: U.S. Pat. No. 5,056,855, entitled "Vehicle Bed Cover Assembly" issued to Moravsky on Oct. 15, 1991; U.S. Pat. No. 5,016,935, entitled "Collapsible Cap for a Pickup Truck Box" issued to Semple on May 21, 1991; U.S. Pat. No. 4,784,429, entitled "Collapsible Camper Top for Pick-up Trucks" issued to Hodges on Nov. 15, 1988; and, U.S. Pat. No. 5,054,841, entitled "Portable Pickup Truck Camper Shell Standard or Roll Bar Model" issued to Zalman on Oct. 8, 1991.
In all of these situations though, the resulting mechanism was so complex that its purpose was averted--to make the shell easier to attach or remove from the pickup.
Going to an extreme was the creation of the tonneau cover which covers only the lower portion of the cargo bed. One such apparatus is described in U.S. Pat. No. 4,792,178, entitled "Truck Tonneau Cover Assembly" issued to Kokx on Dec. 20, 1988.
Although easy to use, the tonneau cover is extremely restrictive on the cargo which can be enclosed and as such it has not won wide acceptance.
In an effort to reduce the weight and expand upon the cargo space available, a variety of tarpaulin or fabric covered shells have been developed, including: U.S. Pat. No. 3,785,694, entitled "Flexible Cover Assembly" issued to Sargent on Jan. 15, 1974; U.S. Pat. No. 4,380,350, entitled "Truck Box Tarpaulin Assembly" issued to Block on Apr. 19, 1983; U.S. Pat. No. 4,310,194, entitled "Tent Camper for Pickup Truck" issued to Biller on Jan. 12, 1982; U.S. Pat. No. 4,756,325, entitled "Collapsible Canopy for Pick-up Trucks" issued to Daniels on Jul. 12, 1988; U.S. Pat. No. 4,955,660, entitled "Test Structure for Pickup Truck" issued to Leonard on Sep. 11, 1990.
Although these tarpaulin and fabric shells are lighter and generally easier to install and remove, the all suffer from deformation and drag due to the forces of wind. As the vehicle travels, or even during a windy day, the fabrics tend to whip and bow causing additional drag to the vehicle and wear on the fabric.
It is clear from the foregoing that there exists a need for an improved cargo bed cover which is easy to install, easy to remove, light weight, and yet resists wind deformation.